1. Field of the Invention
The invention relates to a semiconductor device and a manufacturing method thereof, in which heat sinks are arranged on both sides (i.e., one on each side) of a first semiconductor element on an upper arm side and a second semiconductor element on a lower arm side, and the upper arm and the lower arm are electrically connected by a link portion provided on at least one of the heat sink on the upper arm side and the heat sink on the lower arm side.
2. Description of Related Art
Japanese Patent Application Publication No. 2012-235081 (JP 2012-235081 A) describes a related semiconductor device in which heat sinks (first to fourth thick plate portions) are arranged on both sides (i.e., one on each side) of a first semiconductor element on an upper arm side and a second semiconductor element on a lower arm side, and a link portion (a first thin plate portion) provided on the heat sink on the upper arm side (i.e., the second thick plate portion) is electrically connected to a link portion (a second thin plate portion) provided on the heat sink on the lower arm side (i.e., the third thick plate portion).
Also, Japanese Patent Application Publication No. 2007-27794 (JP 2007-27794 A) describes another related semiconductor device in which heat sinks are arranged on both sides (i.e., one on each side) of a semiconductor element, and the heat sink is cut (i.e., machined) together with a sealing resin body, and a radiating surface of the heat sinks are exposed from the sealing resin body.
The inventors intensively studied an semiconductor device having a structure in which an upper arm and a lower arm are arranged aligned and are electrically connected via a link portion, as described in JP 2012-235081 A.
The results show that the semiconductor device deforms when pressed on from both sides in the alignment direction. For example, the cutting process described above is performed using a cutting tool such as a milling cutter while the sealing resin body is being pressed from both sides in the alignment direction after the sealing resin body has been formed. Therefore, in the cutting process, the semiconductor device is pressed on from both sides in the alignment direction and deforms. As a result, the flatness of the radiating surfaces, and the parallelism of these radiating surfaces, is difficult to ensure. Also, the sealing resin body may end up remaining on the radiating surfaces, depending on the amount of deformation.